Description of problem:
yum-updatesd keeps waking up 10 times per second while it's idle. This is
obviously not a good idea, it eats compute and battery power for absolutely no
reason.
To check this, just do
strace -tt -p <pid of python that runs the updated>
I've not yet been able to find where this is coming from but FC6 really
shouldn't ship with this one

static gboolean
pyg_signal_watch_prepare(GSource *source,
int *timeout)
{
/* Python only invokes signal handlers from the main thread,
* so if a thread other than the main thread receives the signal
* from the kernel, PyErr_CheckSignals() from that thread will
* do nothing. So, we need to time out and check for signals
* regularily too.
* Also, on Windows g_poll() won't be interrupted by a signal
* (AFAIK), so we need the timeout there too.
*/
#ifndef PLATFORM_WIN32
if (pyg_threads_enabled)
#endif
*timeout = 100;
return FALSE;
}

afaik the kernel only sends signals to threads that don't have them blocked. If
python doesn't want anyone but the main thread to get signals, it should just
block signals on all but the main thread and then by nature, all signals will go
to the main thread....